Abstract: An apparatus for preparing a titanium dioxide (TiO2) sol is provided. The apparatus includes a storage unit configured to store an organic solvent mixture containing an aqueous titanium dioxide sol and a dispersing stabilizer, a separation unit connected to and installed at the storage unit and configured to separate the organic solvent mixture into titanium dioxide particles and an organic solvent mixture containing water and the dispersing stabilizer, a circulating solution transfer path connected and installed between the separation unit and storage unit and configured to transfer the titanium dioxide particles separated by the separation unit to the storage unit, and a discharge unit connected to and installed at one side of the separation unit and configured to discharge an organic solvent mixture containing the water and dispersing stabilizer separated by the separation unit.